The feces is suitable like urine as a non-invasive examination sample so that it is broadly used as the sample in several examinations.
Of the aforementioned examinations, the detection of occult blood in the feces is known as the screening method of a digestive disease such as a discharge of blood from a digestive tract and is very important for diagnosis of a hemorrhagic disease such as an ulcer or cancer of the digestive tract.
In the method of detecting the occult blood in the feces, the method (e.g., Japanese Patent Laid-Open No. 125064/1984) based upon the immunological reaction principle, as recently reported, is superior in the points of specificity and sensitivity to the conventional detection method using the guaiac reagent and is noted as a new screening method for the aforementioned disease.
Incidentally, in order to execute the method of detecting the occult blood in the feces on the basis of the immunological reaction principle, it is necessary to sample the feces quantitatively in advance and to suspend the sampled feces in a suitable liquid thereby to prepare a predetermined feces suspension.
This is because the immunological detection reagent is preset to achieve a sensitivity according to a specimen to be anticipated, i.e., the amount of the feces, so that the sensitivity is lowered if the amount of the feces to be examined is too small. On the contrary, too much feces to be examined will cause inconveniences for the transportation or mailing and emit an offensive odor. Moreover, a problem will arise when an excess of the specimen (i.e., the feces) is to be disposed after the examination.
In order to eliminate these difficulties, there have been proposed in the prior art a variety of feces-sampling transport containers. For example, Japanese Utility Model Laid-Open No. 69160/1987 has disclosed a feces-sampling transport container which is equipped with a sampling rod having a notched portion, a recessed portion or a through hole in the vicinity of its leading end.
When the feces-sampling transport container disclosed in Japanese Utility Model Laid-Open No. 69160/1987 is used, a substantially constant amount of feces sample is held in the notched portion, the recessed portion or the through hole formed in the vicinity of the leading end of the sampling rod, so that the amount of feces to be sampled can be limited to a certain extent. It is, however, limitative to control the amount of feces to be sampled, exclusively by the leading end structure of the sampling rod. Depending upon the physical properties of the feces, for example, the sampling amount may get excessive or short.
The feces-sampling transport container having succeeded in eliminating the difficulties of the feces-sampling transport container disclosed in Japanese Utility Model Laid-Open No. 69160/1987 is exemplified by the feces-sampling transport container which is disclosed in Japanese Utility Model Laid-Open No. 42454/1989, as shown in FIG. 18. This feces-sampling transport container is constructed to include: a container body 2 capable of accommodating a liquid 1 for suspending feces; a cap 4 equipped with a sampling rod 3 having at least one of a notched portion, a recessed portion and a through hole in the vicinity of its leading end and capable of being connected to the container body 2 through sealable means; and a dropping portion 6 having a filter 5 therein. The feces-sampling transport container is provided with a stocker portion 8 which is formed by the cap 4, a separating wall 7 for separating the inside of the container into at least two chambers, and the sampling rod 3 extending through the separating wall 7. In FIG. 18, other reference numerals 9 and 10 designate a hole and a notched portion.
In the feces-sampling transport container shown in FIG. 18, the sampling rod 3 is inserted into the feces to be examined to sample a certain amount of feces at its leading end portion. After this, the sampling rod 3 is inserted through the hole 9 of the separating wall 7 into the container body 2. At this time, an excess of feces can be rubbed out by the hole 9. As a result, a constant amount of feces sample can be easily sampled at the notched portion 10.
In the transportation of the feces-sampling transport container, on the other hand, it would be practically convenient to send and/or return the feces-sampling transport container by means of (regular) mailing envelopes. In the case of transportation by the mailing envelope, however, there are usually some limits. According to the Japanese regulations, for example, the thickness of the envelope must not exceed 10 mm. In the feces-sampling transport container disclosed in Japanese Utility Model Laid-Open No. A2454/1989 and shown in FIG. 18, however, the container body 2 is not slender but has a larger diameter than 10 mm. Thus, there arises a difficulty that the feces-sampling transport container cannot be sent and or returned in Japan by the (regular) malling envelope.
The feces-sampling transport container having succeeded in eliminating the difficulty of the feces-sampling transport container disclosed in Japanese Utility Model Laid-Open No. 42454/1989 is exemplified by the feces-sampling transport container disclosed in Japanese Utility Model Laid-Open No. 140468/1990 and shown in FIG. 19. According to this disclosure, in the feces-sampling transport container, a container body 12 charged with a liquid 11 is equipped with a dropping portion 13 at its leading end and has its leading end sealed with a cap 14, and this cap 14 is equipped with a sampling rod 15 to be inserted into the container body 12. This container body 12 is molded into a slender shape, in which is fixed a rubber plug 17 dividing the container body 12 into two chambers and having a hole 16 receiving the sampling rod 15 in a manner to slide on its outer circumference. The cap 14 is press-fitted in the container body 12 through an O-ring 18. The sampling rod 15 is formed with a helical groove 19 at its leading end. The dropping portion 13 is equipped therein with a malt filter 20 and a filter 21.
In addition to the aforementioned feces-sampling transport container, there has been proposed a feces-sampling transport container having a filter, as disclosed in EP-175326 or U.S. Pat. No. 5,246,669.
The feces-sampling transport container, as disclosed in Japanese Utility Model Laid-Open No. 140468/1990, can be sent and/or returned in Japan by means of the (regular) mailing envelope because its container body 12 has an external diameter of about 9 mm. Since, however, the container body 12 is molded in an elongated slender shape, the dropping portion 13 has its leading end portion so reduced in the external diameter that it cannot retain a sufficiently large filtration area (or effective diameter) for the malt filter 20 and the filter 21.
Incidentally, some specimen or feces contains fine particle or a mucus called the mucin. This feces is called the "hard-extraction feces" or "hard-filtration feces" because it is hard to filter when a predetermined amount of specimen is to be extracted for the examination through the filter from its suspension in the aforementioned container.
For the examination of the feces, it is usually necessary to extract four droplets of the specimen through the filter from that suspension. Since there may arise a failure of sampling the specimen droplets or a re-examination, it is preferable to extract some excess of the specimen droplets. According to the aforementioned feces-sampling transport containers disclosed in Japanese Utility Model Laid-open Nos. 42454/1989 and 140468/1990, however, the specimen is hard to extract in a sufficient amount for the examination in case it is the hard-extraction feces or the hard-filtration feces.
The feces-sampling transport container disclosed in EP-175326 belongs to that having the filter at an early stage. Thus, this feccs-sampling transport container does not have any quantitative feces sampling mechanism but has a large container body so that it is not suited for transportation, especially for mailing.
On the other hand, the feces-sampling transport container disclosed in U.S. Pat. No. 5,246,669 is of the new type equipped with the quantitatively feces sampling mechanism. This feccs-sampling transport container is equipped with a mechanism for preventing any pressure rise in the container body when the feces sampling rod is inserted into the container body. However, the disclosure of U.S. Pat. No. 5,246,669 has failed to investigate or hint any solution to the largest problem to be caused in case the feces-sampling transport container is thinned to achieve convenience for transportation or mailing, namely, the problem that the effective filtration area of the filter is not retained so that a sufficient filtered liquid cannot be achieved.
The present invention has been conceived to solve the above-specified problems of the prior art and has an object to provide a feccs-sampling transport container which can have such a convenient usability as to sample a proper amount of feces specimen easily, which is so convenient in transportation that it can be easily sent and/or returned by mailing means such as the envelope means, and which can easily extract a sufficient amount of specimen in a droplet form for the examination from a suspension of feces through a filter no matter what properties the feces might have.